Previous methods of achieving assisted global positioning system (A-GPS) fixes have been subject to degraded performance in networks which make use of repeaters to provide better phone service coverage in a network. Typically, in a method which uses the time difference of arrival (TDOA) to calculate the position of a mobile station (MS), the distance between a mobile station and a base transceiver station/tower (BTS) can be determined given the speed of light and the transmit/receive times of a signal transmission between the BTS and the MS. A BTS holds the radio transceivers that define a cell and coordinate the radio-link protocols with the mobile MS. A cell defines a geographic area and is usually divided into sectors. A sector references a cell which divides its coverage area into several divisions. The number of sectors supported is variable, but it's common for there to be three. However, there exist 1 and 6 sector cells and possibly even 2, 4 and 5 sector cells defined by the radio transceivers held by a BTS. Typically, at least three towers are required to determine the MS position. Multilateration is the name applied to the technique of determining position from a MS-transmitting signal to more than one receiving tower. Forward link multilateration is the name applied to the A-GPS method wherein the MS receives signals from transmitting towers to determine position. Timing is critical to either technique of multilateration as an error of a mere μs in clock synchronization (e.g., among receiving/transmitting towers) can result in an error in MS position determination of about 984 feet. Until now, other network-aided MS position determining methods roughly determined the sources of the signals received by the mobile station. Since these signal source determinations generally don't analyze a great many possible signal sources, error in source determination is likely. This error is propagated through to the determination of the location of the mobile station in that error in the identification of the sources of the signals likely leads to an error in determining the location of the mobile station.
Reference numerals have been carried forward.